There were no survivors from the wreckage of two aircraft that crashed on Mamotswiri peak, near Tzaneen, Limpopo police spokesman Brigadier Hangwani Mulaudzi said.
"We can confirm that the bodies of 13 people, including two children, were found near the wreckage on Tuesday morning," he said,
"The families of the deceased have been informed and are receiving counselling."
The names and ages of those on board both Albatross planes, would be released in due course.
Search and Rescue SA spokesman Johnny Smith said indications were that both planes flew into the mountain, but this was not confirmed.
Rescue personnel had to be hoisted into the area after the crash site was discovered by a police helicopter at 8:15am.
The wreckage was found high up on the peak, Smit added.
Bad weather and low cloud conditions had hampered search and rescue operations on Monday, Smith said.
The planes took off from a landing strip in Tzaneen after an air show on Sunday and were headed to the Rand Airport in Germiston, Gauteng.
Mulaudzi said police and the Civil Aviation Authority would now take over with investigations.
"We are working together to protect the scene, and process information," he said.
Names of those who died on flight ZU MMI
Pilot: Brian Gruar
Marrion Anderson
Maddison Doak
Alexandra Doak
Tess Spence
Louise Warden
Kevin Woolacott
Names of those who died on flight Z5 NJX
Pilot: Peter Gildenhuys
Peter van Oldenburg
Frans Dely
Marietjie de Witt
Stuart van Oldenburg
Linda Pierce